Appendix IV: Fallacies

Appendix IV: Fallacies

A fallacy is a proposition or belief that is based on unsound reasoning –

The campaign for sex equality is misguided; in the world of primates,
the male is always the dominant sex.
(Natural-law fallacy)

The word is understood here, however, in its broader sense to include arguments that are more accurately described as ploys, ruses, deceptions
or simply errors, whether or not they are logically sound –

All law-abiding citizen will agree that compulsory identity cards are a
practical and sensible idea.
(Argument directed at the person)

However they are understood – and whether written or spoken, deliberate or accidental – fallacies can persuade us to believe things we would not
otherwise believe, so it is important that we are able both to recognise and avoid them.

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Affirmation of the Consequent / Denial of the Antecedent

Two sides of the same coin, these fallacies concern conditional propositions of the kind, If A, then B (where A is the antecedent and B, the
consequent) –

If you are in the British Museum (A),
then you must be in London (B).

This proposition is perfectly valid, but the affirmation of the consequent fallacy assumes that we can go on to argue the converse: If B, then A –

If you are in the British Museum (A),
then you must be in London (B).
Therefore, if you happen to be in London
(Affirmation of the consequent, B),
you must be in the British Museum
(Fallacious affirmation of the antecedent, A).

Here is how the fallacy might occur in an argumentative essay –

One of the most important considerations of whether EU membership
is good for Britain must be its effects on employment, and for the last
ten years, at least, unemployment figures have been consistently low.
There are other criteria we need to consider, of course, but in this one
respect we can say that Britain’s membership of the EU has been
beneficial.

If we reduce this to its logical elements, we get –

If membership of the EU is good for Britain (A),
then we would expect to see low unemployment (B)
(Valid, given that we value full employment.)
Therefore, since we do in fact have low unemployment
(Affirmation of the consequent B),
membership of the EU must be good for Britain
(Fallacious affirmation of the antecedent A).

The point, of course, is that low unemployment might be due to factors entirely unrelated to EU membership.

The opposite fallacy, denial of the antecedent, assumes that from If A, then B, we can infer, If not A, then not B –

If you are in the British Museum (A),
then you must be in London (B).
Therefore, since you happen not to be in the British Museum
(Denial of the antecedent, A),
you cannot be in London
(Fallacious denial of the consequent, B).

A possible essay example –

If the government could produce hard evidence to show that speed
cameras save lives (A),
then their appearance on almost every main road up and down the
country might be justified (B).
But since the government has failed to produce such evidence (–A),
we have to conclude that there is no justification for speed cameras (–B).

The argument is fallacious because the government’s failure to produce evidence that speed cameras save lives is not proof that they do not (see
argument from ignorance). There might also be other justifications for speed cameras, such as a reduction in non-fatal road accidents or the
revenue they raise in speeding fines.

Argument Appealing to Authority (argumentum ad verecundiam)

It is perfectly in order to cite authorities to support a point one makes in an argument, just as long as the citation is not presented as proof, a point
of particular importance in disciplines, such as economics, where expertise is not value free. In this respect, it is well to bear in mind the falsifiability
principle advanced by Karl Popper¹ that a truly scientific hypothesis can by definition never be proved but only falsified.

Argument Appealing to Consequence (argumentum ad consequentiam)

This is absurdly to offer the consequences of an argument as its proof –

There must be a God, for otherwise life would be pointless.

Thus God's existence is irrationally postulated on the grounds of the undesirable results (whatever these might be) of His non-existence. We might
similarly ‘prove’ the existence of Santa Claus or the Tooth Fairy.

But appeal-to-consequence arguments are not necessarily fallacious when they are used to justify beliefs rather than prove them. Even so, we
should not simply accept them on face value –

Judge: ‘I am going to make an example of you because there is far too
much of this kind of thing going on.’

By this utilitarian or deterrence theory of justice, a particular punishment is ‘justified’ partly on the grounds of its expected social consequences.
Thus the offender receives a harsher sentence than others who commit precisely the same crime at times when it is less prevalent. The custodial
sentences handed out to looters following the city riots of 2011 are a case in point.

Argument Appealing to Nature (Natural-Law Fallacy)

By the natural-law fallacy, an argument is assumed to be sound because its conclusion resembles a condition in the natural world, or unsound
because it does not –

The campaign for sex equality is misguided; in the world of primates,
the male is always the dominant sex.

The fallacy is a form of the broader naturalistic fallacy of drawing statements of value from statements of fact (‘ought’ from ‘is’): Since X is (or is
not) the case in the natural world, it ought (or ought not) to be the case in the human world.

Those who commit the fallacy, moreover, are rarely consistent in its application, for their choice of natural phenomena to be emulated is very
selective. Many species, for example, defecate wherever the fancy takes them, yet no one seems to suggest that human beings ought to follow
their example. Furthermore, if such things as homosexuality and cosmetic surgery are declared to be ‘unnatural’, then so too are face-to-face
heterosexual copulation and conventional surgery.

Argument Appealing to Novelty (argumentum ad novitatem)

This is to recommend an argument by virtue of its novelty or newness: New, Hurrah!; Old, Boo! Thus were we invited to accept the ‘modern’ policies
of ‘New Labour’. New and modern, essentially descriptive terms, were being used prescriptively to mean ‘better’ or ‘improved’. The National Health
Service has undergone considerable ‘modernisation’ since the 1980s, but it is debatable, to say the least, whether it has undergone a corresponding
improvement. Modernisation, in fact, has virtually become a political euphemism for the implementation of cost-cutting changes. (See also the
opposite, argument appealing to tradition.)

Argument Appealing to Numbers (argumentum ad numerum) / Argument Appealing to Popularity (argumentum ad populum)

These are the closely related ploys of seeking to strengthen an argument by popular appeal –

Welfare benefits should be severely curbed because it is we, the millions
of taxpayers, who have to foot the bill

or by citing the large number of people who accept it –

There are two hundred and fifty million Christians in the world. A religion
with that kind of following can’t be wrong.

The mere fact that millions of taxpayers are paying for something can have no bearing on the merits of what they are paying for, any more than the
number of people who embrace a belief can affect its veracity.

Argument Appealing to Pity (argumentum ad misericordiam)

Justification of an argument is sought here on the grounds of compassion –

As an SS Guard in 1944, he murdered dozens of Jews, but he is now a
very sick man in his nineties and it would not be fair to put him on trial.

His essay isn’t really good enough to pass but he works extremely hard,
so I think we should push it through.

Compassion might be a legitimate factor in the consideration of arguments of this sort, but there is unlikely to be universal agreement on each
occasion.

Argument Appealing to Threat (argumentum ad baculum)

Arguments appealing to threats are often perfectly valid in respect of influencing behaviour –

If you talk to Mummy like that again, you’ll be put in the naughty
chair for ten minutes.
You don’t want to be put in the naughty chair.
So don’t talk to Mummy like that again.

If you drink and drive, you’ll lose your licence.
You don’t want to lose your licence.
Therefore, you shouldn’t drink and drive.

The injustice of a threat, of course, does not affect its validity –

If you don’t hand over your wallet, I'll shoot you.
You don’t want me to shoot you.
Therefore, you should hand over your wallet.

Threats, or threats alone, however, cannot logically affect belief. When the Elizabethan Recusancy Acts set fines and other penalties for Catholics
who refused to attend Anglican services, the most the authorities could hope for was a change in behaviour or a declaration of a change of belief.

Argument Appealing to Tradition (argumentum ad antiquitatem)

It is quite wrong to outlaw fox-hunting; the sport has been a British tradition
for centuries.

The same might once have been said of public executions. (See also the opposite, argument appealing to novelty.)

Argument Directed at the Person (argumentum ad hominem)

This very common ploy attempts to weaken an argument by discrediting its proponent –

He wants Britain to withdraw from the European Union, but the man’s a
reactionary idiot.

Another version is to declare the motives for an argument to be disingenuous or ignoble –

It’s all very well for her to argue that interest rates should rise; she doesn’t
have a mortgage.

It might be perfectly in order to draw attention to the contradictions between people’s behaviour and beliefs, or to expose their motives as selfish,
but neither their behaviour nor their motives can have any bearing on the merits of their actual beliefs. My doctor, for example, might consume sixty
cigarettes a day, but she would still be right to warn me of the dangers of smoking.

The ploy is even more effective when the attack on the person is concealed –

All law-abiding citizens will agree that compulsory identity cards are a
practical and sensible idea.

The logical implication here is that anyone who disagrees must be a criminal.

Ad hominem has several off shoots. 'Guilt by association' attempts to discredit an argument by associating its proponent with infamous others –

‘I think euthanasia can sometimes be justified.’
‘So did the Nazis, as I recall.’

In interrogative form, it can appear as a complex question –

Do you really mean to say you support that Nazi policy of euthanasia?

Another variant is called 'poisoning the well', where the proponent of an argument is discredited before he makes it (the rhetorical equivalent of the
pre-emptive strike) –

Did you know that Councillor Jones has been cautioned by the police for
kerb crawling? I’m also told he beats his children.

The idea here is to prejudice the listener against anything Councillor Jones has to say.

Argument from Ignorance (argumentum ad ignorantiam)

This is the fallacy of assuming that something must be true or false simply because we are ignorant of any proof to the contrary –

Cannabis is perfectly safe. There is no proof that it does any harm.

‘No proof of harm’ is not the same as ‘proof of safety’.

Circular Argument (circulus in demonstrando) (Begging the Question (petitio principii))

A circular argument is one that assumes the very conclusion to be reached, that is, an argument in which the statement or question is absurdly
offered as its own explanation. The simplest example is the petulant reply children sometimes make to unwelcome questions –

‘Why did you bite your brother, Sarah?’
‘Because I did!’

The best satirical example of circularity (or 'begging the question') is probably the notorious catch 22 in Joseph Heller’s novel of the same name –

‘Why can’t I be granted a military discharge?’
‘Because the only grounds for a military discharge is insanity.’
‘But I’m insane!’
‘You can’t be!’
‘Why not?’
‘Because no one who applies for a military discharge can possibly be
insane.’

The fallacy is commonly encountered in religious argument where God is cited as the arbiter of morality –

‘Why should we be good?’
‘Because God tells us to.’

If we press on with the questions, however, we complete the circle –

‘Why should we do as God says?’
‘Because He tells us only to do what is good.’
‘Why should we be good?’

In fact, the very idea of God can have no explanatory value in either scientific or moral inquiry; His inclusion inevitably creates circularity.

Circular arguments can be particularly treacherous where the alleged proof or disproof of something is its own definition –

Astrology is a bogus study because it is not possible for the movement
of celestial bodies to influence human affairs.

Since the belief that ‘the movement of celestial bodies can influence human affairs’ is precisely what astrology is, the argument is circular. In other
words, the ‘proof’ of the worthlessness of astrology is simply a definition of the study itself –

Astrology is a bogus study because it is astrology.

Or in young Sarah’s words –

Astrology is a bogus study because it is.

We might want to challenge astrology by saying that it is wrong in its belief that the movement of celestial bodies can influence human affairs, but
this a point of view, not a reasoned deduction; it is the inclusion of the word because that makes the argument circular.

Complex Cause

This is the ploy of citing only one cause of a phenomenon when there are others at least equally important –

The fall in which my client broke his leg was caused by loose carpeting
at the top of the staircase.

True, but it was 3.00 a.m. and he hadn’t switched on the light. And he hadn’t switched on the light because he didn’t want to wake the family. And
he didn’t want to wake the family while he was burgling their house.

Complex cause is common in advertising where information that would make an offer less attractive is omitted –

Simply complete the course of twenty lessons, and if you are not speaking
fluent French by the end, we guarantee to refund you the cost of the course
in full.

What we are not told is that the lessons become inordinately more difficult such that the majority of students fail to complete. In other words, what
‘causes’ the refund is not simply the completion of the course plus the failure to master French, but the completion of the very difficult course plus
the failure to master French. (See also joint effect.)

Complex Question (Loaded Question)

A complex question is two questions in one, that is, what should be two questions is conflated into one in such a way as to implicate the recipient,
usually in something reprehensible. Any direct answer to the complex (or loaded) question thereby commits the recipient to an affirmative answer to
the unspoken question it implies, as in the much-cited example –

Have you stopped beating your wife yet?

The preliminary question Have you ever beaten your wife? is not only unasked but is assumed to have been answered affirmatively. In the same way,
the interviewing police officer does not ask Did you kill him?, but Why did you kill him? or What have you done with the body? The irate parent asks –

How much longer do you intend to disturb everyone with that noise?
(Disturbance there might be, but it is hardly the intention.)

And we might have noticed that sales staff no longer ask the simple question Can I help you?, but the complex question How may I help you? (See
also false dichotomy.)

Contradiction

A contradiction comprises two or more logically incompatible statements or beliefs. Sometimes the contradiction, called an oxymoron, is made
deliberately for rhetorical or humorous effect (cruel kindness, deafening silence, living death, anarchy rules). On other occasions, it exposes the
proponent's boorish indifference to reason. In Nazi anti-semitic propaganda, for example, Jews were held to be both 'subhuman' and the 'lowest
form of humans'. But most contradictions are neither amusing nor malevolent; they are simply misleading. Religious doctrines are notorious for
them, such as the inconsistent Christian beliefs in divine creation and eternal life. (Eternity has neither beginning nor end, so nothing that has
been created can possibly be eternal.)

Fallacy of Causation from Chronology (post hoc, ergo propter hoc)

Post hoc, ergo propter hoc (‘after this, therefore because of this’) assumes that two events must be causally connected merely because they occur
in succession –

Government policies might have put the brakes on inflation, but they have
been disastrous for jobs. Within the government’s first term of office,
unemployment rose to 15 per cent.

This might be acceptable as part of an argument, but a causal connection between government policies and job losses is not established by the
mere chronological succession of the phenomena.

The fallacy is also the root of superstition –

Mrs Smith from Woking passed this chain letter on and won £3m on the
Lottery the following Saturday. Mr Harris from Neasden ignored it, and
broke his nose three days later when he stepped on his garden rake.

Leaving aside the problem that both Mrs Smith and Mr Harris appear to have received their letters before they were written, their mixed fortunes are
seen not simply as occurring after their treatment of the letter, but because of it.

However, post hoc is a fallacy deeply rooted in the human psyche, and we are all probably affected by it more than we care to admit. There is an
apocryphal story of a beautiful woman who had the misfortune to be widowed twice, each of her husbands having been struck dead by lightning.
Everyone agreed that this was no more than bizarre coincidence but, in spite of her efforts and charms, she never married again.

Fallacy of Equivocation (No-True-Scotsman Fallacy)

This is the common fallacy of defending a discredited argument by changing the meaning of one or more of its terms. Rather than admit his or her
error, the proponent will try to accommodate it by a redefinition –

‘All Scotsmen love whisky.’
‘But Robbie McCullum doesn’t like whisky.’
‘Well, he’s no true Scotsman, then.’

Thus the definition of Scotsman changes from the assumed ‘man from Scotland’ to the rather dubious 'whisky-loving man from Scotland'.

Again –

‘You can’t get a university degree unless you can express yourself well
in written English.’
‘But Tom has a degree and he’s dyslexic.’
‘Where did he graduate?’
‘Melchester.’
‘Well, you don’t call that a university, do you?

Instances of the fallacy occasionally appear in politics. When no weapons of mass destruction were discovered in Iraq following the invasion of 2003,
the 'justification' for the continued occupation became the search for ‘weapons-of-mass-destruction programmes’.

Fallacy of Extreme Vividness

This is the irrational assumption that, because a personal (and usually unpleasant) experience is particularly vivid, it is more likely to occur again –

Jill: ‘I’m thinking of buying an Acme computer. All the reviews have
been excellent.’
Jack: ‘I wouldn’t if I were you. I bought one last year and it gave me
nothing but trouble.’

No amount of positive reviews will persuade poor Jack to buy another Acme computer. As far as he is concerned, his one vivid experience is worth
more than all the expert evidence and consumer satisfaction put together. But like the post hoc fallacy, extreme vividness seems to be firmly
embedded in our nature (once bitten, twice shy) –

After that terrifying emergency landing I experienced last year, I swore
I’d never fly again.

The twentieth-century philosopher, Bertrand Russell, made a distinction between ‘knowledge by acquaintance’ and ‘knowledge by description’, and
it is certainly true that the events we witness or experience make a greater impression upon us than those that are merely described or reported to
us.² But the fallacy of extreme vividness can be criticised as egocentric as well as illogical. For example, people will sometimes declare their loss
of faith in God following the untimely death of a loved one when the identical tragedies of innumerable others had apparently left their faith untroubled.

Fallacy of Moderation (Fallacy of Compromise, Fallacy of the Golden Mean)

This is to assume that the wisest answer or course of action must be the middle of two extremes –

The seller wants £1,000 and the buyer has offered £500.
Therefore, the item must be worth £750.

I think fascism is bad and I think communism is bad.
Therefore, liberalism must be good.

Compromise is often expedient, but we should accept the possibility that one extreme might on occasions be entirely right and the other entirely
wrong. If Mary says the European Union comprises 27 states³, while John says it comprises 35, it would be nonsense to conclude that the correct
number must be the halfway 31. We should beware of construing the word extreme always in a negative way, just as we should moderate in a
positive way.

False Dichotomy (False Dilemma)

Similar to the complex question, this is the ruse of presenting only two options when, in fact, there are more –

‘You are either with us or against us.’ (George W. Bush)
What about the option of neutrality?

Are you going to study hard on this course or just waste your time?
What about studying satisfactorily and having some fun too?

Gambler’s Fallacy

This is the fallacy of assuming that an untypical trend must soon correct itself –

‘I’m going to invest £10,000 in Megatron.’
‘But their shares have been tumbling for weeks.’
‘Precisely! So they must be due to go up soon.’

If we take the standard example of repeatedly tossing a coin, the gambler’s fallacy consists in believing that the coin has a memory, that it will
somehow remember past results and decide that the time has come for a change. In fact, each toss is unconnected with all others so that, even
after a run of ten consecutive heads, the result of the next toss will still be 50:50.

Hasty Generalisation / Sweeping Generalisation

These are the opposite fallacies of generalising from the particular (hasty generalisation) and particularising from the general (sweeping
generalisation) –

Men who wear jewellery should not be trusted. I’ve met a few of them,
so I should know. (Hasty generalisation)

The McPherson Report found the Metropolitan Police guilty of
institutional racism. John is an officer in the Met, so he must be a
racist. (Sweeping generalisation)

Joint Effect

This is the common ruse of citing one event as the cause of another when a wider perspective could reveal both events to be the effects of another
cause –

The rail strike will cause massive disruption to commuters.

Very likely, but both the disruption and the strike might sequentially have been caused by the employer’s imposition of inferior working conditions,
job cuts or unsafe working practices. (See also complex cause)

Straw Man (Ignoratio Elenchi, Irrelevant Conclusion, False Scent, Red Herring)

The many names of this fallacy bear testimony to its prevalence, and it is probably the most commonly used device in the politician’s box of tricks,
namely, the tactic of dodging one question by answering another –

Interviewer: ‘But, minister, won’t charging motorists to use motorways
and enter city centres discriminate against the less wealthy drivers?’
Minister: ‘We have to face the fact that congestion on our roads is reaching
intolerable proportions. Unless we act soon and act decisively, we are going
to reach gridlock.’

Thus the argument is made for reducing traffic congestion, which has nothing to do with the interviewer’s question.

The perpetrators of this ploy misrepresent their opponents’ arguments (setting up straw men) the more easily to defeat them –

Anti-abortionists have no respect for the rights of women.
(This is a misrepresentation of the anti-abortionist position which would deny
women one right.)

The Conservative Party cares nothing for the working class.
(This ignores the one-nation principle of the Tory left.)

Communism will never work. If everyone receives the same income,
there’ll always be some people who believe they deserve more.
(Communism does not maintain that everyone should receive the same income.)

Tautologies

A tautology is a statement that is necessarily true, or true by definition (e.g. All bachelors are unmarried). By contrast, a contingent statement is
one whose truth or falsity can be empirically verified (e.g. The Titanic sank in the north Atlantic in April 1912). The difference is logically crucial.
The Titanic could have sunk in a different place, at a different time, from different causes or might never have sunk at all. Bachelors, on the other
hand, cannot conceivably be other than unmarried.

A tautology, therefore, cannot possibly be fallacious since its assertion is implied in the meaning of one or more of its words: being unmarried is
partly what it means to be a bachelor. Rather, the fallacy consists in mistaking tautologies for contingent statements –

It is a law of nature that only the fittest survive.

On first appearance, this statement looks like a contingent one, but closer inspection shows it to be tautologous. The error is exposed when we
try to define fittest. For the statement to be a contingent one – telling us something of value about the world – the word fittest must mean
something more than simply ‘those that survive’. So what, in fact, is meant by fittest? It cannot mean ‘most physically strong’ because the
butterfly has survived while Tyrannosaurus rex has not. It cannot mean ‘most fearless’ or ‘most courageous’ because most species survive by
the instinct of flight rather than fight. It cannot mean ‘most selfish’ or ‘most competitive’ because many species, including human beings, survive
as much by cooperation as competition. It cannot mean ‘most healthy’ because the obese are better equipped to survive famines.

In the absence of a substantive definition, then, fitness means nothing more than ‘the ability to survive’. If John is a healthy rugby player in peak
condition and Joe is an immobilised victim of rheumatoid arthritis, John clearly runs the greater risk of breaking his neck. In this context, therefore,
Joe’s disability becomes a survival mechanism. In other words, everything that survives must by definition be the fittest, and this is all our statement
claims –

It is a law of nature that only those that survive are equipped to survive.

Teleological Fallacy

A teleological argument is one in which the principal cause of something is its purpose or reason (from the Greek telos 'end' or 'purpose'). It is
uncontentious when applied to human affairs: We were in Brighton for the day when we were caught in a sudden downpour, so I bought a cheap
umbrella.

Expressed formally –

I want to stay dry in the rain.
It started to rain.
Therefore, I bought an umbrella.

What 'caused' the purchase of the umbrella was the intention of staying dry. Teleology thus presupposes an intelligent agent with a reason for acting.

But such arguments become fallacious when extended to the material world –

Conditions X, Y and Z are sufficient to sustain human life.
The planet Earth has conditions X, Y and Z.
Therefore, the planet Earth was designed to sustain human life.

Was designed to is a non sequitur; all that follows is can.

Teleology in nature was a subject of much debate in the nineteenth century between theologians and evolutionists –

Does the giraffe have a long neck in order to eat the leaves at the top
of the tree, or does it eat the leaves at the top of the tree because it
has a long neck?4

But teleological arguments are rarely encountered today, being virtually confined to creationist or intelligent-design groups that deny evolutionary
theory .⁵

Wrong Direction (Putting the Cart Before the Horse)

This is the error of mistaking cause for effect. An historical example given in the Wikipedia entry is the medieval belief that lice were conducive
to good health. The belief stemmed from the observation that proportionately fewer sick people had lice than healthy people. But we know now
that lice react adversely to high body temperature and consequently leave febrile hosts. Good health, then, was the cause of the lice and not,
as was believed, the lice the cause of of good health.

Again –

Coalition forces should remain in the country until the insurgency is
quelled.

The statement postulates the insurgency as the reason of the presence of coalition forces when the presence of coalition forces is more plausibly
the reason for the insurgency.

____________

¹ Karl R. Popper, The Logic of Scientific Discovery, Hutchinson of London, 1977.
² It is worth observing here that vicariously creating this sense of vividness is an indispensable technique for the writer of narrative. There is a tale of
a newspaper editor rebuking a journalist for the latter’s submission of a lacklustre article on social deprivation: ‘Don’t preach to me about poverty;
show me the rats!’ (See styles of writing and showing, not telling.)
³ Correct at the time of writing.
⁴ Attributed to the naturalist, Philip Henry Gosse (1810–88).
⁵ For examples of the teleological fallacy and its exposure, see Wikipedia entries on the watchmaker analogy, Hoyle’s fallacy and the weasel program.

Grammar and Style in British English:

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